Factorio Forums

1. What did you do?
   Set up a decider combinator to compare "anything" to 0 and pass through that "anything".
2. What happened?
   Solid fuel ran into the negative numbers but was still being passed through.
   
3. What did you expect to happen instead? It might be obvious to you, but do it anyway!
   Solid fuel signal should have been considered false and a different signal should have passed through.
4. Does it happen always, once, or sometimes?
   It didn't happen with any of the other signals I was using before solid fuel, but it seems to happen consistently with solid fuel. (Possibly this is because those signals all stopped at 0, due to stack size...?)

Log file

Not a Bug, as per the discussion following this post.

Outputting Anything when the condition is not using Each will output a single signal out of the input signals. In particular, Anything will pick the first input signal in some game defined order that roughly resembles the order the items appear in the crafting UI.
To make the decider work as you expected use Each in the condition; then outputting Anything will pick among the signals that pass the condition.

...Yeah, so I figured that out and was coming back here to rescind the bug report.

Kind of confusing, though; maybe the tooltip on "Anything" could specifically mention that it inputs the one that passed if you are using each?